Relapsing polychondritis

病史

Study requested to rule out occult infection and assess disease activity in a thirteen year old boy before bone marrow transplantation.

檢查結果

Multiple foci of FDG uptake including ears, larynx, trachea and bronchial tree, costal cartilage, knees as well as right ankle and foot. Calcifications of laryngeal structures and costal cartilage. Tracheostomy. Mild spleen activity probably related to the inflammatory process.

DDx

Relapsing polychondritis

Sarcoïdosis

Wegener’s granulomatosis

診斷

Relapsing polychondritis

討論

Relapsing polychondritis (RP) is a rare systemic disease of unclear etiology characterized by recurrent inflammation of cartilaginous tissues including in particular external ear, nose, peripheral joints, larynx and tracheobronchial tree. Development of autoimmunity against cartilage components is tought to be the pathogenic mechanism.

RP is more common in caucasian adults during the fourth or fifth decades. One study estimates that pediatric-onset RP represents <5% of the reported cases. The clinical manifestations are variable but commonly imply auricular chondritis, arthritis, nasal chondritis and costal chondritis. The features are similar between adults and children One report identifies a higher incidence and severity of laryngotracheobronchial involvement in children, with greater need of tracheostomy.

Roles of PET/CT FDG

Several authors have demonstrated utility of PET/CT FDG for diagnosis and monitoring of the therapeutic response. It is a powerful tool for early diagnosis and to assess distribution of lesions. Correlation between findings on PET/CT FDG and disease activity on a clinical basis has been reported. Metabolic activity is thought to be related to inﬂammatory cells such as neutrophils, activated macrophages, and lymphocytes, who take up large amount of glucose as a result of an increased metabolic rate.